Clutch and brakes for sewing machine



May 31, 1966 A. E. MAROLA ETAL 3,253,685

CLUTCH AND BRAKES FOR SEWING MACHINE Filed July 25, 1963 5 Sheets-Sheet 1 AMEmco EMAQOLA 3 an NORMAN W. TARR 7am/m,

ATTORNEYS May 31, 1966 A. E. MAROLA ETAL 3,253,685

CLUTCH AND BRAKES FOR SEWING MACHINE Filed July 25, 1965 5 Sheets-Sheet 2 NORMANWSTARR mvemons flnamco Emma ATTORNEYS y 1966 A. E. MAROLA ETAL 3,253,685

CLUTCH AND BRAKES FOR SEWING MACHINE 5 Sheets-Sheet 5 Filed July 25, 1963 Anemco BMAROLA 6- NORMAN LU. STARR mvemons BY%W'L W M W ATTORNEYS May 31, 1966 A. E. MAROLA ETAL 3,253,685

CLUTCH AND BRAKES FOR SEWING MACHINE W m m A. z l .1 AN 9 S 9 G e 3 N l c 7 E v 6 w 2 a e w 6 cw 3. S O N t Mm a w 6 v 7 R e n M 5 D T n Qfi 2 5 7 9 9 m /o k .l G 8 I a a I .5 9

STOP POSFHON Filed July 25, 1965 WHZNG MAGEQM UMQ NG' DlRGRQM I: G. 8 $10? POS\T\ON DEWINC: EKIGQGEMENT AMEmco EMAQQLA Nozmsu w. STARR ATTORNEYS y 1966 A. E. MAROLA' ETAL 3,253,685

CLUTCH AND BRAKES FOR SEWING MACHINE Filed July 25, 1963 5 Sheets-Sheet 5 I3 P1641 3th I 53 v'la 19 NEUTRAL I POSWiON SINGLE STlTCH OPERATION,

loo 0 .101. 42 m 15 F]. G. wmme DIAGRAM r 6. '4 wmme DIAGRAM NEUTRAL Posmou SmGLE STITCH oPERnTmN INVENTORS AMERKIO E. MRROLA 6s NORMAN U0. STARR ATTORNEYS United States Patent 3,253,685 CLUTCH AND BRAKES FOR SEWING MACHINE Amerieo E. Marola and Norman W. Starr, Torrington,

Conn., assignors to The Torrington Company, Torrington, Conn., a corporation of Maine Filed July 25, 1963, Ser. No. 37,622 14 Claims. (Cl. 192-18) The invention, of which the following is a detailed specification, relates to a clutch control for sewing machines. In the efficient and speedy foot control of the operation of a motor-driven sewing machine, it is desirable to operate the clutch mechanism under a variety of conditions. The ordinary engagement of the clutch mechanism can be used to control the speed. It is also impor- :tant that the sewing operation be capable of stopping instantly. There are also circumstances under which it is desired to make a single stitch by the single revolution of the main or driven shaft.

One of the objects of this invention is to provide a treadle-operated clutch by which the motor power is directly connected to the main shaft of the sewing machine.

A further object of the invention is to provide a friction brake on the hand wheel of the sewing machine correlated with the clutch operating mechanism in such manner as to maintain braking action on the wheel Whenever the clutch is disengaged.

A still further object of the invention is to effect mechanical disengagement of the clutch and its braking in a predetermined position of the main shaft.

It is also possible by this invention to effect a clutching engagement which will permit a single revolution of the main shaft followed by disengagement of the clutch and stoppage of the machine.

With these and other incidental objects of the invention, it has been illustrated by way of example on the accompanying drawings on which:

FIGURE 1 is a vertical section of the clutch mechanism for a sewing machine;

FIGURE 2 is an enlarged vertical section of the cor related clutch throw-out mechanism on line 2-2 of FIG- URE 3;

FIGURE 3 is anenlarged vertical section on the line 33 on'FIGURE 1;

FIGURE 4 is an enlarged detail elevation of the pivotally-mounted brake means;

FIGURE 5 is a partial vertical section on the line 55 of FIGURE 1;

FIGURE 6 is a detail perspective view of the solenoidcontrolled micro switches;

FIGURE 7 is a schematic diagram of the parts when in a stop position;

FIGURE 8 is the corresponding wiring diagram for FIGURE 7;

FIGURE 9 is a schematic diagram of the parts in driving engagement;

FIGURE 10 is the corresponding wiring diagram for FIGURE 9;

FIGURE I l is a schematic diagram of the parts in a neutral position;

FIGURE 12 is the corresponding wiring diagram for FIGURE 11;

FIGURE 13 is a schematicdiagram of the parts in a single stitch position;

FIGURE 14 is the corresponding wiring diagram for FIGURE 13; and

FIGURE 15, appearing in the sheet embodying FIG- URE 3, is a perspective view of the treadle.

Primarily the invention consists in controlling the clutch mechanism and drive of a motor-driven shaft on a sewing machine, so that the desired objects may be obtained 3,253,685 Patented May 31, 1966 by simple and effective means. 0n the accompanying drawings, the preferred form has been illustrated to include the following features.

There is a main frame or housing 11 forming part of the sewing machine structure. The end of the housing carries a brake housing 12. This has a conical friction face 13, forming a brake upon the clutch.

The customary main or driven shaft 14 is suitably mounted in the housing 11 by a ball bearing 1-5.

The outer end of the shaft 14 has a loosely journ'alled pulley In. This pulley is driven by means of a belt 17 in the direction shown by the arrow on FIGURE 1.

The pulley 16 has an inner flange 18 which cooperates with the drive clutch to apply power to the shaft 14.

A drum 19 is loosely journaled on the shaft 14. The drum has a flange 20.

A hand wheel 21 is fitted around the drum and against one side of the flange 20. Adjacent the hub of the hand wheel 21, there is a clutch disc member 22. This has a conical face fitting frictionally in engagementwith the face of the flange 18 of the pulley 16. On the opposite side of the drum is a brake shoe 23 having a conical face. This face is brought into frictional engagement with the brake housing 13. A series of through bolts 24 run through the clutch disc member 22, the hand wheel 21, the flange 2t and the brake shoe 23, as shown in FIG- URE 1.

The inside face of web 25 of the drum 19 has a slotted stop adjustment plate 28, formed with projecting lugs 27 attached by cap screws.

Slightly spaced from the plate 28, the shaft 14 carries a collar 26, which may be adjusted into a selected position around the shaft 14. This collar 26 carries a dog 29, which is engaged by the lugs 27. Three compression springs 106, seated in holes incollar 26, bear against the outer face of flange 31.

A loose brake collar 30' is provided with two flanges 31 and 31', one 31' of which is bolted tightly to the web 25 of the drum 19. A second spaced flange 31 provides a track for the operation of a cam roller 43. The inside face of the flange 31 has a cam lobe or boss 32.

Adjacent the flange 51, the shaft 14 carries a loosely journaled clutch throw-out bearing 33, having a wear plate or flange 34.

Beneath the brake housing 12, the housing 11 has projections 35 in which three spaced bearings 36, 37 and 33 form journals for a pivot shaft 39. Between bearings 36 and 37 there is journaled a clutch lever 40. This clutch lever has a yoke 41, by which the clutch throw-out wear plate and hearing are moved toward the pulley 16, with which the clutch face 22 is brought into engagement.

A rock arm 4-2 is pivotally carried between the bearings 37 and 3 8. The upper end of the rock arm carries a roller 43. This roller 43 travels continuously within the spacing between the inner faces of the flanges 31 and 3-1 of the loose brake collar 30 and is in operative engagement with the cam lobe 32 as indicated by FIGURES l and 3.

The housing 11 also forms the support for a bracket 44, through which a treadle control rod 4 5 is slidable, as shown in FIGURE 4. The housing 11 at its base forms a bearing 415 through which a rock shaft 47 projects, as shown in FIGURE 2. Outside of the base of the housing 11, the projecting end of the rock shaft 47 carries a bell crank lever 48. The treadle control rod 45 extends down to a bearing on a pivot pin 49 intermediate the ends of the bell crank lever 48. A coil spring 5ft surrounding the upper portion of the rod 45 is adjustably held between This cam bar is journaled in the bottom of the frame 105 and the slide bearings 68. j,

The frame 105 has a bracket 54 which has a pivoted rock arm 55. The free end of the rock arm 55 carries a finger 56 freely movable within a notch 57 on the nearer side of the cam bar 53.

- The rock arm 55 carries a pin 58 which projects upwardly.

The frame 105 carries pivot screws 59 and 60. These carry gudgeons' 61 and 62 which form a pivotal mounting for a spring-loaded brake 63 which brake is engageable with the periphery of the hand wheel 21. The bottom side of the brake 63 carries an abutment 64.

The pin 58 extends below the rock arm 55, where it supports a spring 65. The spring is held in compression by the bolt 66 screwed into bracket 54 at its lower end.

An adjustable stop nut 67 forms an abutment against bracket 54. 1

The. sewing machine housing 11 is normally mounted on a table (as seen in FIGURE 15). To connect the clutch control to a foot treadle, the end of the lever 48' has a hole 69. This receives a hook 70 on the end of a rod 71. An eye on the end of rod 71 is pivoted to the front or toe end of a rocking treadle 72. The treadle 72 is pivotally mounted on a bracket for foundation 7'3. Operation of the treadle rocks the shaft 47 in the direction desired. This in turn provides vertical movement for the control rod 45 and the sliding cam bar 53.

The clutch yoke 41 is offset centrally at 74, where it is journaled on the shaft 39 between bearings36 and 37. Yoke 41 has a depending extension 75 on which is mounted a transverse pin 76 carrying a pendant link 3 supporting a cam follower 77. The follower 77 moves into and out of the depression 78 on the side of the cam bar 53. In this manner the yoke is rocked in a clockwise direction (as seen in FIGURES 1 and 2) to move the clutch disc member 22 and thus bring the driven shaft 14 into engagement with the "clutch member 18. The pendant -link 103 is further connected to the depending extension 75 by a screw 110, the threaded end of which projects through a slot 109 in the extension 75 and is threaded into the pendant link 103. The screw 110 is surrounded by a coil spring 104 which is compressed between the extension 75 and a first nut 107 threaded on the screw 105. A second nut 108 is also threaded on the screw 110 between the extension 75 and the point at which the screw 110 is threaded into the pendant link 103. The spring 104 acts against the first nut 107 and the extension 75 to pull the second nut 108 against the extension 75 and to bias the pendant link and the cam follower 77 towards the extension 75.

The clutch is adjusted by altering the position of the second nut 108 which effects the spacing between the extension 75 of the yoke 41 and the pendant link 103 which carries the cam follower 77. The spacing between the extension 75 and the pendant link 10-3 is inversely proportional to the amount of clockwise (as seen in FIGURES 1-2) movement of the yoke 41 when the cam follower 77 is removed from the depression 78 in the cam bar 53.

Initially the machine drive is in neutral and disconnected from the clutch and drive shaft 14. This condition exists when the treadle 72 is in its central position (as seen in FIGURE 11), or at any time when the operators foot is removed from the treadle. At such time the pressure of the spring 65 against the stop lever 56 pushes the pin 58 upward and causes the pivotally-mounted spring-loaded brake 63 to bear on the periphery of the hand wheel 21. This prevents accidental rotation of the hand wheel and driven shaft 14, precluding accidental rotation of the latter in the central position of the treadle.

By depressing the toe of the foot treadle 72, the rock shaft 47 is rotated to pull down the treadle control rod 45. It follows that cam bar 53 is also lowered and its cam surface moves the cam follower 77, resulting in movement of URES 1 and 2). This then strikes the clutch throw-out washer or wear plate 34, its bearing 33 and the brake collar-flange 31. As a consequence, the drum 19 moves to the right (as seen in FIGURES l-2) and the clutch disc member 22 engages the face 18 on the pulley 16. The main shaft 14 is thus caused to rotate by engagement of the stop adjustment plate 28 with the clutch dog 29 on the driven shaft 14. Almost simultaneously the cam bar 53 pulls down on the lever 55, thus allowing the pivotallymounted spring-loaded brake 63 to release the hand wheel 21. The main shaft 14 is therefore set in rotation. This initiation of operation is entirely'mechanicaland does not allowthe operation of any of the auxiliary electric circuits.

The housing 11 carries a two-position microswitch79 adjacent the treadle control rod 45. The control rod 45 has a finger 80 which on rising comes in contact with a blade operator 79' of the switch 79, thus releasing the latter from a first to a second position.

Driven shaft 14 carries a cam 81 which rotates and strikes an operating lever of a two-position microswitch 83.

A solenoid-84 is mounted within the housing 11 and adapted for intermittent operation. This solenoid has a coupling 85 forming part of a shaft 86 which projects through an opening of the housing. The end of the shaft 86 carries a friction plate 87. Adjacent the friction plate 87 is a cam plate 88. Beyond the cam plate is a cam 89. The cam plate 88 and the cam 89 are keyed for rotation on the shaft 86. The cam 89 has a cam release pin 90.

Below the solenoid 84 there is mounted on the housing 11, a release solenoid 91. A shaft of this solenoid projects through the housing wall and at its end carries a release arm 92. This release arm may be brought into the path of the release pin 90 by the operation of the solenoid 91.

A drum 93 on the shaft 86 has three axially spaced depressions 94, 95', 96.

Fixedly mounted around the drum 93- are a twoposition microswitch 97 for the solenoid 84; a two-position microswitch 98 for the single stitch operation solenoid (as seen in FIGS. 13 and 14); and a two-position microswitch 99 for the release solenoid 91.

For limiting the motion of the driven shaft 14 to a single revolution, a two-position microswitch 100 is mounted on the forward end of the treadle 72. This switch 100 is operated by depression of a small toe lever 101.

In depressing the heel of the treadle for stoppingthe operation (as seen in FIGS. 7-8), the finger 80 is raised into contact with the blade operator 79' and the two-position microswitch 79 is moved to the second of its two-positions.

With the microswitch 97 in the first of its two-positions, contact of the operating lever 82 of the switch 83 with the cam 81 on the driven shaft 14 establishes alternating positions of switch 83.

With finger 80 in contact with blade operator 79', placing switch 79 in its second position, and with switches 97 and 83 in their first positions current is applied to the solenoid 84. This rotates the shaft 86, causing the microswitches 97-99 to move to their second positions (as seen in FIGURES 7-8) and inserts a resistor into the circuit to prevent burn-out of the coil of solenoid 84. Rotation of the cam 89 brings the high point of the cam into contact with the lower roller 102 of the rock arm 42. This pivots needle and awl position of the sewing machine, the stop seen in FIGS. 1142), finger 80 moves out of contact with blade operator 79' placing switch 79 in its first position, 79 moves to closed contact, causing current to flow through single stitch microswiteh 100 and to the release solenoid 91, which returns the solenoid 84 to position of rest by the solenoid release arm 92 hitting the solenoid cam release pin 90, restoring the microswitches 9799 to their first positions (as seen in FIGS. ll-12) and resulting in an electrical as well as mechanical neutral condition.

By single stitch sewing or for automatic positioning in less than one stitch, the toe lever 101 enclosing switch 100 and mounted on the toe of the treadle 72, is depressed by the operator, moving the microswitch 100 to its second position (as seen in FIGS. 13-14), also depressing the toe of the treadle 72 and engaging the clutch, as previously described. This causes the shaft 14 to rotate and causes the cam 81 to contact the operating lever 82 of switch 83, operating the solenoid 84, which rotates the solenoid shaft 86 and moves microswitches 97-99 to their second positions, inserting a resistor into the solenoid circuit.

The brake 13. 23 is actuated in automatic stop position in the same manner as previously described, except for one difference. The operator is holding the clutch 18, 22 engaged with toe treadle 72 at the same time that the brake mechanism 13, 23 is actuated by the solenoid 84. This causes a mechanical interference which is then relieved by compressing the spring 104 between the first nut which is threaded on the screw 110 that is threaded into the pendant link 103, and the depending extension 75 of the clutch fork 41, preventing damage to the mechanical linkage. Upon release of the toe lever 101 by the 0perator, the single stitch microswitch 10% operates the same release solenoid cycle as previously described.

What we claim is:

1. In a sewing machine or the like, a shaft, means supporting the shaft for rotation, a combined pulley and clutch member loosely journaled on the shaft, control means comprising a driving dog adjustably secured to the shaft, a collar loosely journaled on the shaft, a brake drum mounted on the collar, means adjustably secured to the brake drum which are engageable with the driving dog, a clutch face mounted on the brake drum and being engageable with said pulley and clutch member, a clutch lever, means mounting said clutch lever for pivotal movement, said clutch lever being operatively engageable with the collar, cam means, and means mounting said cam means for reciprocable movement to pivot said clutch lever, whereby reciprocable movement of said cam means controls the engagement and disengagement of said combined pulley and clutch member with said shaft.

2. The combination as defined in claim 1 wherein there is further included adjustable cam follower means mounted on said clutch lever and engageable With said cam means.

3. In a sewing machine or the like, a shaft, means for supporting .the shaft for rotation, a combined pulley and clutch member loosely journaled on the shaft, control means comprising a driving dog adjustably affixed to the shaft, a collar loosely journaled on the shaft, a brake drum mounted on the collar, means adjustably secured to the brake drum which are engageable with the driving dog, a clutch face mounted on the brake drum and being engageable with said pulley and clutch member, a clutch lever, means mounting said clutch lever for pivotal movement, said clutch lever being operatively engageable with the collar, brake means, means mounting said brake means for pivotal movement, said brake means being operatively engageable with the periphery of said brake drum, cam means, and means mounting said cam means for reciprocable movement to pivot said clutch lever and brake means, whereby reciprocable movement of said cam means controls the engagement and disengagement of said combined pulley and clutch member with said shaft 6 and the engagement and disengagement of said brake means with the periphery of said brake drum.

4. The combination as defined in claim 3 wherein said brake means includes mounting means, a brake pivotally mounted on said mounting means, an actuating pin for said brake afiixed to a finger member which is pivotally mounted on said mounting means, a spring located between said mounting means and said finger member for biasing said actuating pin into engagement with said brake, and wherein said finger member is operatively engageable with said cam means.

5. In a sewing machine or the like, a shaft, means for supporting the shaft for rotation, a combined pulley and clutch member loosely journaled on the shaft, control means comprising a driving dog adjustably affixed to the shaft, a collar loosely journaled on the shaft, a brake drum mounted on the collar, means adjustably secured to the brake drum which are engageable with the driving dog,

a brake shoe mounted on one side of the brake drum and being engageable with said means for supporting the shaft, a clutch face mounted on the opposite side of the brake drum and being engageable with said pulley and clutch member, a clutch lever, means mounting said clutch lever for pivotal movement, said clutch lever being operatively engageable .with the collar, first cam means, means mounting said first cam means for reciprocable movement to pivot said clutch lever whereby reciprocable movement of said first cam means controls the engagement of said combined pulley and clutch member with said shaft, said collar having a cam track, a rock arm mounting a first cam follower at its one end and a second cam follower at its opposite end, means mounting said rock arm for pivotal movement, the first cam follower on said rock arm being engageable with the cam track of said collar, second cam means, and means mounting said second cam means for rotary movement to engage said second cam follower on said rock arm to pivot said rock arm, whereby rotary movement of said second cam means controls the engagement of said brake shoe with said means for supporting the shaft and the disengagement of said combined pulley and clutch member from said shaft.

6. The combination as defined in claim 5 wherein there are further included mechanical means for providing said reciprocable movement and electrical means for providing said rotary movement.

7. In a sewing machine or like shaft, means for supporting the shaft for rotation, a combined pulley and clutch member loosely journaled on the shaft, control means comprising a driving dog adjustably afiixed to the shaft, a collar loosely journaled on the shaft, a brake drum mounted on the collar, means adjustably secured to the brake drum which are engageable with the driving dog, a brake shoe mounted on the side of the brake drum facing said means for supporting the shaft, a clutch face mounted on the other side of the brake drum, a clutch lever, means mounting said clutch lever for pivotal movement, said clutch lever being operatively engageable with the collar, first cam means, means mounting said first cam means for reciprocable movement to pivot said clutch lever whereby reciprocable movement of said first cam means controls the engagement of said combined pulley and clutch member with said shaft, said collar having a cam track, a rock arm mounting a first cam follower at its one end and a second cam follower at its opposite end, means mounting said rock arm for pivotal movement, the first cam follower on said rock arm being engageable with the cam track of said collar, solenoid-operated cam means, and means mounting said solenoid-operated cam means for operative engagement with the second cam follower on said rock arm to pivot said rock arm whereby engagement of said solenoid-operated cam means with said second [cam follower controls the engagement of said brake shoe with said means for supporting the shaft and the disengagement 0; said combined pulley and clutch member from said s aft.

8. The combination as defined in claim 7 wherein there is further included adjustable cam follower means resiliently mounted on said clutch lever and engageable with said first cam means.

9. The combination as defined in claim 8 wherein there is further included means to actuate said solenoid-operated cam means to engage said second cam follower Causing said brake shoe to be engaged with said means for supporting the shaft and said combined pulley and clutch member to be disengaged from said shaft after only a single revolution of said shaft has been completed.

10. The combination as defined in claim 8 wherein there is further included means to actuate said solenoidoperated cam means .to engage said second cam follower causing said brake 'shoe to be engaged with said means for supporting the shaft and said combined pulley and clutch member to be disengaged from said shaft regardless of the position of said first cam means.

11. In a sewing machine or the like, a shaft, means for supporting the shaft for rotation, a combined pulley and clutch member loosely journaled on the shaft, adjustable control means comprising a driving dog adjustably affixed to the shaft, a collar loosely journaled on the shaft, a brake drum mounted on the collar, means adjustably secured .to the brake drum which are engageable with the driving dog, a brake shoe mounted on the side of the brake drum facing said means for supporting the shaft, a clutch face mounted on the other side of the brake drum, a hand wheel mounted on the brake drum between said brake. shoe and clutch face, a clutch lever, means mountingsaid clutch lever for pivotal movement, one end of said clutch lever being operatively engageable with the collar and the opposite end of said clutch lever having adjustable cam follower means resiliently mounted thereon, brake means, means mounting said brake means for pivotal movement, said brake means being operatively engageable with the periphery of said hand wheel, first cam means, means mounting said first cam means for reciprocable movement to engage said cam follower means to pivot said clutch lever and brake means whereby reciprocable movement of said first cam means controls the engagement and disengagement of said combined pulley and clutch member with said shaft and the engagement and disengagement of said brake means with the periphery of said hand wheel, said collar having a cam track, a rock arm mounting a first cam follower at one of its ends and a second cam follower at its opposite end, means mounting '8 said rock arm for pivotal movement, the first cam follower of said rock arm being engageable with the cam track of said collar, solenoid-operated cam means, and means mounting said solenoid-operated cam means for operative engagement with the second cam follower on said rock arm to pivot said rock arm whereby engagement of said solenoid-operated cam means with said second cam follower controls the engagement and disengagement of said brake shoe with said means for supporting the shaft and the engagement and disengagement of said combined pulley and clutch member with said shaft regardless of the position of said first cam means. 12. The combination as defined in claim 11 wherein there is further included means to actuate said solenoidoperated cam means to engage said second cam follower causing the engagement of said brake shoe with said means for supporting the shaft and the-disengagement of said pulley and clutch member from said shaft after only a single revolution of said shaft has been completed.

13. The combination as defined in claim 12 wherein there is further included treadle means connected to said first cam means, the operation of said treadle means causing recipr'ocable movement of said first cam means, and said means to actuate said solenoid-operated cam means comprise electric switch means mounted upon said treadle means.

14. The combination as defined in claim 13, wherein said means to actuate said solenoid-operated cam means further comprise a cam means affixed to said shaft which are operatively engageable with electric switch means connected in series with said switch means mounted upon said treadle means.

References Cited by the Examiner UNITED STATES PATENTS 938,474 11/1909 Glass.

958,710 5/1910 Biggert 19224 1,048,840 12/ 1912 Littlefield. 1,449,327 5/1923 Jaycox et a1. 19293 X 1,884,162 10/1932 Osman 19217'X 2,024,293 12/ 1935 Keall et al 19218 X 2,496,793 I 2/1950 Herbers 19217 2,625,248 1/ 1953 Gerdhof et al. 19293 X DON A. WAITE, Primary Examiner.

DAVID J. WILLIAMOWSKY, Examiner.

B. W. WYCHE III, Assistant Examiner. 

1. IN A SEWING MACHINE OR THE LIKE, A SHAFT, MEANS SUPPORTING THE SHAFT FOR ROTATION, A COMBINED PULLEY AND CLUTCH MEMBER LOOSELY JOURNALED ON THE SHAFT, CONTROL MEANS COMPRISING A DRIVING DOG ADJUSTABLY SECURED TO THE SHAFT, A COLLAR LOOSELY JOURNALED ON THE SHAFT, A BRAKE DRUM MOUNTED ON THE COLLAR, MEANS ADJUSTABLY SECURED TO THE BRAKE DRUM WHICH ENGAGEABLE WITH THE DRIVING DOG, A CLUTCH FACE MOUNTED ON THE BRAKE DRUM AND BEING ENGAGEABLE WITH SAID PULLEY AND CLUTCH MEMBER, A CLUTCH LEVER, MEANS MOUNTING SAID CLUTCH LEVER FOR PIVOTAL MOVEMENT, SAID CLUTCH LEVER BEING OPERATIVELY ENGAGEABLE WITH THE COLLAR, CAM MEANS, AND MEANS MOUNTING SAID CAM MEANS FOR RECIPROCABLE MOVEMENT TO PIVOT SAID CLUTCH LEVER, WHEREBY RECIPROCABLE MOVEMENT OF SAID CAM MEANS CONTROLS THE ENGAGEMENT AND DISENGAGEMENT OF SAID COMBINED PULLEY AND CLUTCH MEMBER WITH SAID SHAFT. 